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Penumbra-overture shader errors?

02-02-2008, 06:03 AM

Does anyone get this game to run correctly with the new OpenGL engine?
After I read the "X-plane it works" article i thought that most shaders and opengl features were supported and running well with 8.1.
But now when I try to run Penumbra with the default settings it crashes with a segfault. To not get the game to segfault you have to disable shadows completely.
Now the game doesn't crash... But with anything but "shaders: very low" items, walls, and other objects doesn't render correctly and thus makes it impossible to progress as you can't actually see the things you´r supposed to interact with. They mostly become invisible or flickers badly.
The weird thing is that the game works with shadows and shaders on high with 8.40.4 just with some minor gfx bugs on reflective metals etc.

Now to my question: Is it only me that have these problems or is it quite a few shaders/features that is missing in the ati-drivers after 8.40.4?
You can download the demo here: http://www.penumbra-overture.com/

I just want to know if the problem is on my end and not in the drives. (I have a x1900XT BTW)

Comment

The problem would be in the drivers I'm afraid. While I suspect that ATI's driver handles "correct" shader specifications, it definitely doesn't handle cases where the shader code's presuming a default behavior for normals, etc. where there really isn't- and NVidia's driver does the "right" thing and ATI's does something different, but technically not incorrect. There's some sharp edges in the ARB shader program spec (the assembly language type API into shader programming) that NVidia just kind of smooths over- but ATI lets you screw yourself on. That's not a bad thing, mind- but it makes for annoyances for the studios doing development and the users playing the games.

Comment

The problem would be in the drivers I'm afraid. While I suspect that ATI's driver handles "correct" shader specifications, it definitely doesn't handle cases where the shader code's presuming a default behavior for normals, etc. where there really isn't- and NVidia's driver does the "right" thing and ATI's does something different, but technically not incorrect. There's some sharp edges in the ARB shader program spec (the assembly language type API into shader programming) that NVidia just kind of smooths over- but ATI lets you screw yourself on. That's not a bad thing, mind- but it makes for annoyances for the studios doing development and the users playing the games.

Well that could be the problem... But the game works with less errors on 8.40.4 (nearly none). Were the shaders more "forgiving" before the OpenGL update?
Maybe I should try it out on my windows drive to see if I problem have the same problem there.

Comment

Well that could be the problem... But the game works with less errors on 8.40.4 (nearly none). Were the shaders more "forgiving" before the OpenGL update?
Maybe I should try it out on my windows drive to see if I problem have the same problem there.

8.41's a new codebase for the actual OpenGL pieces of code, from my understanding of things. I think they might have kept some parts of the shader framework, but not knowing that for sure I'm not going to venture a guess either way. Especially not knowing what all the studio used in rendering API calls. Having said this, there's lots of things that were more "forgiving" with the older codebase- and there's currently still API edges that are missing from the new one that were present in the older codebase, perhaps not properly implemented in some cases, but enough to do something resembling what they're supposed to.

Comment

I just wanna confirm - exactly the same problem with latest driver and my X800PRO AGP. So for sure this is driver problem. And question: did You use demo (as I) or full retail version - there are some patches for it and maybe this fix the problem?

Comment

I just wanna confirm - exactly the same problem with latest driver and my X800PRO AGP. So for sure this is driver problem. And question: did You use demo (as I) or full retail version - there are some patches for it and maybe this fix the problem?

I used the demo version too. There were some patches to the full version but they mainly seems to fix some slowdowns and sound problems that were not present in the demo.
If i get around testing the demo with windows and if it doesn't have the same error I can at least sit this one out till it's fixed. I will get back to you on that.

Edit: Tried it out in windows. Now the shadows work and doesn't crash the game. But the shader errors is still there. How ever they only seems to be present in the first scene of the game.